Continuous tube crack-off machine



June 16, 1953 c. EISLER CONTINUOUS TUBE CRACK-OFF MACHINE 3 Sheets-Sheet 1 Filed Dec. 6, 1950 INVENTOR. [HARM-1r Emu EA nrro/i MEy June 16, 1953 c. EISLER 2,641,870

CONTINUOUS TUBE CRACK-OFF MACHINE Filed Dec. 6, 1950 x 3 Sheets-Sheet 2 INVENTOR. (HA/2 1. EJ' E/J'L ER 17791! NE y June 16, 1953 c. EISLER 2,641,870

CONTINUOUS TUBE CRACK-OFF MACHINE Filed Dec. 6, 1950 3 Sheets-Sheet 5 mmvrozg. 6/ 445! 5/. erg

Patented June 16, 1953 UNITED STATES PATENT -OFFICE I 2,641,870 CONTINUOUS TUBE CRACK-OFF MACHINE Charles Eisler, South Orange, N. J.

Application December 6, 1950, Serial No. 199,380

2 Claims.

This invention relates to the art of cracking off tubes. In the accompanying drawings and description below, the machine and method of the present invention are described, providing a continuous crack-off operation including the automatic repetition of the process during each revolution of the machine.

The invention provides for continuous auto.- matic crackingofl' of glass tubing to desired predetermined lengths without the necessity of stopping the operation for indexing or similar purposes.

The invention provides for the utilization or combination of cooling jets and burners in an arrangement whereby the glass tube to be cracked 011' and the crack-off tool are brought to the temperature required for an ideal crack-off operation.

In the drawings:

Fig. 1 is a top plan view ing the invention,

Fig. 2 is an elevational, partly sectional, view thereof, 7

Figs. 36 inclusive are elevational schematic views illustrating successive steps in the cracking-off process, said figures containing Roman numerals denoting the position of the parts in stations correspondingly marked in Fig. 1,

Figs. 7-10 inclusive are elevational schematic views illustrating the application of the process for cracking off very short lengths of tubing,

of a machine embody Fig. 11 is a side elevational view of a form of crack-01f tool embodying the invention, having height adjustment means,

Fig. 12 is a fragmentary top plan view thereof, taken on line |2|2 of Fig. 11, and

Figs. 13-15 inclusive are schematic elevational views of crack-off tools which may be used in carrying out the invention, shown in the crackoff operational engagement with tubes. 1

The drawings illustrate a practical embodiment of the invention in a machine (Figs. 1 and 2) having continuously rotating spider and glass tube chucks and parts adapted for use in con'- nection therewith; it will be apparent, from the present description, that the invention may be ries the stanchions l5 supporting upper spider B on which are mounted chucks ll, each chuck including sleeve I8, cone l9 and jaws (Fig. 2). The chucks may be of any of the convenient iorms'of construction well known to those skilled in the art to which the invention relates. The jaws 20 may be closed by hand lever 2| when not rotating, and automatically when in rotation in operation by engagement of the lift-roller 23 carried by the chuck opening bracket 24 with the lift-cam rail 22.

The lift cam rail 22 is mounted on bracket 25 slidable on uprights 26 and 2'! connecting upper and lower plates 28 and 29 of frame 30, which is mounted on support 30a. secured to table l0.

- The slidable bracket 3|, with swivel stop plate used in connection with machines having other forms of continuously rotating spiders and chucks, within the scope of the invention as defined in the appended claims.

As shown in the drawings, the machine comprises a table I0, having legs II, the table having mounted thereon the bearing [3 for the main vertical shaft l2, to which lower spider I4 is keyed or otherwise secured. The spider |4 car- 32 extending under the chucks, serves as a stop for the glass tubing to predetermine the length of crack-off required. Stop plate 32 may be pivotally secured to the bracket 3| for movement into and out of the position shown in Fig. 2 in any suitable or convenient manner. For example, the construction in my prior Patent No. 1,828,493, October 20, 1931, may be employed. In said patent, one plate member 32 is shown secured to another member 33 by means of a spring 3| with suitable stops 35 and 36 to prevent excessive movement in either direction. The bracket 32 may be secured to the member 33 by a suitable arrangement so that it will be yieldable against the tension of a spring in one direction and will be prevented from excessive rotation by stop members which correspond with the stops 35 and 36 of Patent No. 1,828,493, just referred to. This arrangement would prevent a wedging of the parts or the breaking of the tube if it should move past the stop plate 32, or should contact the same circumferentially instead of at the very end thereof. In such case, the bracket 32 would yield in the same manner as the member 32 of applicants prior Patent No. 1,828,493 and would yield responsive to the force exerted thereon. Brackets 25 and 3| are each adjustable as to height by nuts 33 on vertical screw rod 34. Spider I4 is rotated continuously by motor 35 and belt and pulley transmission 36, 31, 33, driving worm 39 in mesh with worm gear 40 on drive shaft 4|. On shaft 4| is mounted pulley 42 connected by belt 43 to pulley 44 on countershaft 45. On shaft 45 is keyed worm 46 engaging worm gear 41 mounted on shaft I2 and serving as a suppor mesh with bevel gear 50 on vertical shaft 5| journalled in the upright support. 52. On shaft 5| is mounted spur pinion 53 engaging spur gear 54, which runs on anti-friction means such as thrust ball bearings in gear seat 55 mounted on support 56. Gear 54 engages gears 51 on vertical shafts 58 which carry the upper gears 59 connected by pinions 60 to gears 6! on sleeves it of chucks 11. Thus, as soon as the spider is set in motion, the chucks commence to rotate. The above or other driving, mechanism can be disconnected from the motor 35 by hand clutch lia on shaft 4!. For trial and adjustment, the spiders and clutches can be turned by hand wheel 4lb. I

The cracking-off process, below described, is illustrated in Figs. 3-10 inclusive.

The stock tubing T inserted into the chuck l? is held by the closed jaws 29. As the spider revolves, the jaws are opened at position I by cam 22 and the tubing is allowed to slide down until stopped by plate 32, at which timeva pilot light, such as pilot S6,, ignites burner tiwhich heats the tubing at the point where it is to be cracked off, while the air jet es fed from air ducts tilt of air manifold I55 may be used to prevent the tubing from being overheated above that point (Fig. 3). At position 11 (Fig. 4) this process is continued. At position III (which is the crack-oh position- Fig. 5) the heated tubing comes in contact with the crack-off toola bevelled disc 65 of heat-resisting material, the rim of which, by reason of itsv lower temperature, causes the tube to crack off, the burner 52 being for the moment extinguished by automatic valves while air jet. plays on the rim. of the disc 65 to insure lowest temperatures. of the remaining tube end is annealed to eliminate internal stresses, and to smooth the rim.

Figs. 7-1.0- inclusive illustrate the. crack-off process for cracking off tubes of inconsiderable length for example, of less than one-half inch. In such cases, there is substantial risk of overheating the end which is to be cracked off- Careful adjustment of the cooling jets is necessary. The cooling jets 53 may therefore be operated continuously whereas (Figs. 36 for long crack-ofis,

iey may be intermittently non-active. This is At position IV (Fig. 6), the lower part I largely a matter determined in operation, accord- I tating glass tube bears up against the rim of the disc, the friction causes the disc to revolve so that the entire periphery of the glass tube is touched by the comparatively cold disc. By reason of its free bearing on its mounting, the disc therefore does not have any abrasive or scoring effect and cracking is caused solely by the sudden cooling of the glass.

The crack-off tool shown in Fig. 14 may be sub-, stituted for that shown in Fig. 13 and comprises the diamond til set in holder 68 and rigidly mounted in support 16. In this case, again. the crackingcfi is aided by the difierence in temper ature, although, byreason of the holders fixed position, the diamond may have a slight scoring effect on the heated glass tube. In Fig. 15, the crack-off tool consists of a blade 7| having the slightly concave edge I 2 and securedto holder 13 which may, in turn, be fixed to support 76 or the like. As the blade is not rotatable, it may have a slight scoring eifect on the rotating tube; cracking oi? is again accomplished with a difference in temperature. Annealing and some slight glazing of the crack-ofi rim of the retained tubing may be effected at position IV (Fig. 6). This additional heating has the effect of freeing the glass from internal stresses. With some kinds of tubing, especially the thin-wal=led and small diameter type, this operation may be omitted. The

cracked part of the tubing drops immediately into chute M (Fig. 5).

The complete disc crack-ofi tool shown in Figs. 11 and 12 comprises disc on ball bearings 15 journalled in support 76 which is integrally connested by bracket 'i'i with sleeve part '18, the latter being freely rotatable on shaft 19. The sleeve it is kept vertically in place by screw 80 engaging circular groove 3! in shaft 19. The upper half of shaft 19 is threaded and is slidable in main bracket E32, rotation of shaft it'being prevented byscrew 83 engaging slot 8 of shaft '39. Vertical adjustment of the position of cracleofi disc 65 is effected by raising or lowering shaft i9 by means of nuts 35 and 85. When making contact with the glass tube, the disc 85 swing resiliently responsive to coil spring 81 connected to pin 38 of swinging bracket 7? and pin 39 in the fixed main bracket t2, the back swing of disc t5 being limited by adjustable screw t8 having jam nut 9i, which is threaded in arm 92 of sleeve '38. The screw Bil-bears against the stop member 93 secured to circular rail St to which main bracket the disc, the nozzle 63 will remain incorrect relation thereto.

The burners 62 for heating the glass tubes are carried by the burner-spider 9? which is co-rotatable with and slidable on shaft [2 by means of key and keyway $28- and 99. Gas and oxygen are fed to the burners by ducts itii through the usual rotary valve Nil-592 and mixertube ms. The burners thus continuously follow the chuck with the glass tubes, the only stationary device being the cracking-off device and associated parts of bracket 25.

'Air for cooling is supplied from an outside air compressor (not shown) through tube H34 to the circular air manifold I85 having branch ducts 1 I03 to nozzle 3each duct being provided with a valve 52? whereby the air flow can be regulatedor shut oi? as desired.

The burners are lit as they pass the pilot flame 63 to which gas is fed (from an outside source) .i by the duct 'Hi.

th burner-spider 91' so that the burners and air nozzles may be adjusted vertically an equal amountby raising and lowering the spider 91, which can be effected by turning the hand knob 69 on shaft H9 in. bearing III on spider it.

This will turn the bevel pinion H2 and gear H3 mounted on sleeve H4, which is threaded on inner sleeve H5 slidable on shaft !2 and resting By turning the sleeve" on the hub of spider 91. I it which abuts the burner spider I9 up or down,

the spider i accordingly raised or lowered, The

device described is one of several means which may be used for height adjustment of the burners.

In Fig. 1, the machine is shown as provided with sixteen chucksevery four positions yielding on crack-off (Figs. 1, 3-6)-or a total of four crack-offs for every revolution of the spider. By combining some of the operations or dispensing therewith, a lesser number of chuck positions would be required for completion of each crack-off operation.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In an apparatus for cracking glassware, a bracket adapted to be mounted upon a carrier and having a vertical bore, a threaded shaft extending vertically through the bore of said bracket and being freely slidable vertically therein and having a vertical groove, a pin carried by said bracket and engaged in said groove and preventing rotation of the shaft in the bracket, nuts upon said shaft above and below said bracket serving to shift the shaft vertically and said nuts being engageable with the upper and lower ends of the bracket to grip the bracket therebetween and secure the shaft in a vertically adjusted position, a support carried by said shaft, a post carried by said support and extending upwardly in laterally spaced relation to the support and the bracket, a crack-01f member carried by said post, and a pipe carried by said support and provided with a nozzle directed towards the crack-01f member.

2. The structure of claim 1, wherein the support consists of a sleeve rotatably fitting about the threaded shaft, the post being supported from the sleeve by an arm extending between the sleeve and the post, there being a groove formed about the shaft within the sleeve, a screw carried by said sleeve and engaged in the groove and preventing movement of the sleeve vertically on the shaft, a spring urging the rotation of the sleeve about the shaft in one direction, an arm extending from said sleeve and carrying the tube, and an adjustable member for limiting the rotation of the sleeve in an opposite direction carried by said arm.

CHARLES EISLER.

References Cited in the file of this patent UNITED STATES PATENTS 

